Hay and straw for your bunnies The diet pyramid for rabbits Hay and straw are the most important diet you can give your rabbit. It must live mainly from hay and straw, and in fact 80% of its diet must consist of hay and straw. As this diet pyramid shows (shown below), it should actually only have 10% green a day and this also applies in the summer, although you could quickly be tempted by all the delicious grass that you think the rabbit should have. No, it is definitely not a good idea to replace hay and straw with grass, even in summer. We made this mistake once and it had consequences, so now we will tell you how important it is to give as much hay and straw as possible. If the rabbit gets too much grass, it can risk getting too much gas in the stomach, which can result in GI Stasis, and it can be fatal for the rabbit. As a general rule, the rabbit should eat a pile of tightly packed hay / straw that is the size of it itself. This gives a better visual view of how much hay and ...